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        function countDown(time) {
            var nowTime = +new Date(); // 当前时间
            var inputTime = +new Date(time); // 预设的时间
            var times = (inputTime - nowTime) / 1000; //将剩余时间转换成秒
            var d = parseInt(times / 60 / 60 / 24); //天
            d = d < 10 ? '0' + d : d;
            var h = parseInt(times / 60 / 60 % 24); //时
            h = h < 10 ? '0' + h : h;
            var m = parseInt(times / 60 % 60 ); //分钟
            m = m < 10 ? '0' + m : m;
            var s = parseInt(times % 60 ); //秒
            s = s < 10 ? '0' + s : s;
            return d + '天' + h + '时' + m + '分钟' + s + '秒';
        }
        console.log(countDown('2022-7-22 18:00:00'));
        
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